A damping force adjustable shock absorber is provided between a wheel side and a vehicle body side, which move relatively to each other, of a vehicle, for example, a four-wheeled motor vehicle. The damping force adjustable shock absorber is configured to absorb, for example, vibration in an up-and-down direction generated during a travel. As the damping force adjustable shock absorber, there has been known a damping force adjustable shock absorber including an electromagnetic damping force adjustment device configured to variably adjust the damping force in accordance with, for example, travel conditions and behaviors of a vehicle (for example, see Patent Literatures 1 and 2).